A highly efficient code division multiple access power amplifier of parallel amplification architecture exhibits power added efficiency of 17% and adjacent channel power ratio less than -51 dBc at an output power of 16 dBm. The output impedances of the low/high-power amplifier chains are very low because the collector impedances of the "OFF-state" power heterojunction bipolar transistors are low a...
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A high frequency millimeter-wave voltage-controlled oscillator (VCO) has been designed, manufactured and tested in InP single heterojunction bipolar transistor technology. The fully integrated fundamental differential VCO features high operating frequency up to 80 GHz with low phase noise about -118 dBc/Hz at 1-MHz offset and 5% tuning range. The VCO consumes only 95-mW power at a power supply of ...
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This paper presents a fully differential inductor-capacitor voltage-controlled oscillator (LC-VCO) with a new differentially-tuned varactor structure. The proposed LC-VCO has lower phase noise and better robustness to the injected common-mode noise than the differentially-tuned LC-VCO using the previous antiparallel structure. The LC-VCO implemented using 0.5-μm SiGe BiCMOS technology is t...
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In this paper, a new parallel-coupled-line microstrip band pass filter (BPF) improving the harmonic suppression performance of the second harmonic signal (2fo, twice the passband frequency) is described. It is found that the desired passband performance is improved and the harmonic passband signal is diminished by enforcing the consecutive patterns in coupled-line and increasing the num...
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In this letter, spurious passband suppression in microstrip coupled line band pass filters by means of split ring resonators (SRRs) is demonstrated for the first time. By etching SRRs in the upper substrate side, in close proximity to conductor strip, strong magnetic coupling between line and rings arises at the resonant frequency of SRRs. This inhibits signal propagation in the vicinity of that f...
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Parallel-coupled microstrip filters are designed to suppress spurious response at twice the passband frequency (2fo) with a uniform dielectric overlay. The overlay dielectric is used to equalize the modal phase velocities of each coupled stage. Based on the method, we have a large degree of freedom in choosing thickness and permittivity of the overlay dielectric. The image impedances of...
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Wideband coplanar-waveguide (CPW) bandpass filters based on the cascade of CPW lowpass and highpass periodic structures are proposed. The upper and lower stopband characteristics of proposed bandpass filter can be easily designed by separately adjusting the lowpass and highpass sections, respectively. Specifically, two wideband CPW bandpass filters with sharp roll-off at passband edges and good st...
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A new digital phase shifter design at X-band is presented. The phase shifter operates based on converting a microstrip line to a rectangular waveguide and thus achieving the phase shift by changing the wave propagation constant through the medium. As a proof of principle, a 3-b phase shifter has been designed and constructed using PIN diode switches. An average insertion loss of 1.95 dB and phase ...
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In this letter, a novel predistortion topology using a tunable resonator is presented. The core of the circuit is a series tunable resonator employing a reverse biased varactor diode. The junction capacitance of the varactor diode increases with RF input power, effectively shifting the resonant frequency of the circuit. This results in the amplitude and phase deviations at the frequency of operati...
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Dispersion curves for the shielded Sievenpiper "mushroom" structure are obtained by means of multiconductor transmission-line (MTL) theory. This inherently quasitransverse electromagnetic mode (quasi-TEM) analysis is used to quickly and accurately calculate the dispersion of the lowest pass-band and several of the upper pass-bands. The first pass-band reveals dual mode behavior, supporting one for...
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Electromagnetic crystal (EMXT) surfaces are modeled with effective surface impedance method. Effects of oblique incidence are studied using a technique similar to the waveguide simulator method for analyzing infinite phased array. Numerical results are compared with an analytical model. EMXT samples are characterized by open-ended waveguide reflection measurements using different aperture sizes (W...
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A novel planar dual balun for doubly balanced star mixer is presented. The balun consists of two identical Marchand baluns using coupled microstrip lines. It shows the amplitude imbalance within 1.2 dB and the phase imbalance within 180±1.5° over 1.2 to 2.8 GHz. The star mixer using a pair of the suggested balun has the conversion loss about 6 dB in the band.
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Balanced topology in radar front-end is presented, which can reduce Tx leakage to receiver drastically. The balanced radar front-end which is composed of a differential cross-coupled oscillator, two Lange couplers, and a Wilkinson combiner is implemented using commercially available InGaP/GaAs heterojunction bipolar transistor technology. The tuning range of voltage control oscillator is 320 MHz f...
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By etching longitudinal slots on the top metallic surface of the substrate integrated waveguide (SIW), an integrated slot-array antenna is proposed in this letter. The whole antenna and feeding system are fabricated on a single substrate, which takes the advantage of small size, low profile, and low cost, etc. The design process and experimental results of a four-by-four SIW slot array antenna at ...
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We report the first demonstration of high-Q embedded inductors fabricated using a thin-array-plastic-packaging (TAPP) technology. The TAPP technology provides a platform that integrates digital, analog, RF integrated circuits, along with high-performance passive components for system-in-package implementation. Embedded inductors ranging from 14 to 300 nH were fabricated. All the inductors with ind...
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This letter introduces a new efficient S-parameter extraction technique by exploiting through-reflection-line calibration. The technique will facilitate the modeling of multilayered RF passives using the hybrid mode matching and finite element method. With the proposed technique, a passive component is viewed as a series of cascaded transmission line discontinuities along the direction that is per...
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